The present invention relates in general to air bag deployment systems for automotive vehicles, and, more specifically, to a door support panel structure that has an energy transmitting hinge formed integral with an air bag chute.
Air bag deployment chute assemblies have been put into commercial use for the passenger side of an instrument panel of automotive vehicles. The chute assembly couples an air bag module (typically containing a folded bag and chemical propellants for inflating the bag on command) to a door support panel (i.e., substrate) of the instrument panel. A typical structure for a chute assembly includes a tubular outer wall, one or more door flaps, and one or more hinge members connecting the door flaps to the outer wall. The hinge can be formed with a dual curved configuration that allows the hinge to straighten out as the air bag is deployed.
In copending published application US2010/0109296A1, a hinge element is disclosed that extends between a skirt wall of the air bag chute tube and one edge of a door support panel, and that includes a pair of pivoting elements and an arm extension. A first pivoting element is formed with a downwardly directed curve having one end connected to the inner side of the skirt wall and the other end connected to the second pivot element. The second pivot element is formed with an upwardly directed curve having one end connected to the first pivot element and the other end connected to an extension arm that extends upwards to the edge of the door support panel. During deployment of the associated air bag, the integrated structure allows energy forces presented to the door support panel to be partially dissipated into the structure via the hinge element.
The air bag module is typically required to be mounted with its top edge in a horizontal plane so that the chemical reaction and air bag expansion can be properly directed and controlled. The door support substrate, however, is typically not horizontal. Instead, it usually slopes from the center of the vehicle toward the passenger side of the vehicle. Since the door flap(s) and hinge member(s) follow the shape of the door support substrate, they are also not horizontal. As a result, the deployment forces from the expanding air bag can create a torque on the hinge member that could impair the hinge operation or even cause breakage of the hinge which reduces the dissipation of energy into the skirt wall.